The typical leash used to control a pet consists of an elongated strap, or lead, which attaches to a pet's collar, and some type of grip or handle which the handler grasps in order to control the pet attached to the lead. With a common leash, the pet is free to move around an area defined by the length of the lead. The length of the lead is not normally adjustable although many people simply wrap excess lead length around their hand when they desire to decrease the pet's freedom of movement. This can be damaging to the hand and is thus undesirable. However, adjustable length leashes are desirable because, when greater restriction of the pet's movement is required, such as when walking the pet through a busy street or a crowded walkway, or when another animal appears and makes the pet uneasy, the handler can readily adjust the length of the lead in order to lessen the pet's freedom of movement and keep the pet under control. Because of the degree of control it provides to the handler, an adjustable length leash is also useful in training a pet.
Common in the marketplace today are retractable leash devices wherein the lead is wound around a spring-biased spool retained within the handle portion of the leash device. The spring bias ensures that slack in the lead is constantly taken up by the spool; however, the length of the lead may be fixed by operating a switch located on the handle that causes a pawl to engage the spool and stop its biased rotation. Because of their relatively complex construction, these devices are more complicated to manufacture and therefore much more expensive than the common leash. Also these devices are more likely to wear out and break due to the multiple components employed in their construction.
Attempts have been made to provide adjustable length leashes which are more simple to manufacture and therefore inexpensive. These leash devices include a handle portion having a grip from which extends a thin neck having an upper flange and a lower flange. A lead is connected to the handle portion, and the length of the lead may be adjusted by wrapping the lead around the neck until the desired lead length is achieved. The upper and the lower flanges are designed in an attempt to prevent the lead from de-spooling from around the neck.
This leash, while inexpensive and simple to manufacture, has its own drawbacks. For example, having two flanges capable of retaining the lead creates a situation where the force of the pet's pull may alternate between the upper flange and the lower flange when the lead length is adjusted. This is uncomfortable and can cause soreness in the handler's wrist. Also, the thin design of the neck requires a large amount of winding in order to adjust the length of the lead or to wind the lead for storage. Additionally, this leash device fails to address the desirable concept of a locking mechanism by which the length of the lead, when extended or retracted to the desired length, can be more fixedly secured so as to ensure that, even when a pet forcefully pulls upon the lead, the lead will not have a tendency to de-spool from the neck portion.
Improvements over the prior art may also be achieved by concentrating on the ergonomics of the handle design. Specifically, it is desirable, although not addressed by the prior art, that regardless of what length the lead is retained at, the forces exerted on the lead and handle portion be focused substantially straight through the wrist and arm of one using the adjustable length leash, thereby substantially eliminating any torque upon the user's wrist.
Thus, the need exists in the art for an improved adjustable length leash which allows the handler to selectively adjust and secure the length of the lead extending from the handle portion, which is simple and inexpensive to manufacture, having few or no component parts readily susceptible to breaking or wearing out, and which focuses the forces exerted on the lead and handle portion straight through the wrist and arm of the handler.